China’s unmanned Tiangong-1 space lab is hurtling towards Earth and is expected to re-enter Earth’s atmosphere on Sunday, April 1 at 12.15pm EDT (4.15pm GMT), according to the Aerospace Corporation, give or take nine hours.

The non-profit company said: “The world is watching as Chinese space station Tiangong-1 hurtles towards Earth and makes a fiery reentry.

“Chances that space debris will hurt anybody are extremely slim, although when and where the space station’s remains will land is still unknown.”

The European Space Agency has predicted a slightly different reentry time of 11.25pm on April 1, however the forecast window runs from the afternoon of April 1 to the early morning of April 2 and is highly variable.

ESA issued a statement today: “The space debris team at ESA have adapted their reentry forecast over the last 24 hr to take into consideration the conditions of low solar acitivy.

“New date received overnight gave further confirmation that the forecast window is moving to later on 1 April.”

As the sun’s activity is weaker than predicted, the atmosphere did not balloon as much and therefore Tiangong-1 has experienced less drag and descended more slowly than expected, ESA said.

The predicted reentry timeframe was originally between March 29 and April 2, however the timeframe has now been narrowed and it is expected to fall to Earth later than expected.

As of midday, Tiangong-1 was orbiting at an altitude of 167km and tumbling towards Earth at a speed of 16,500 mph.

When the space station reaches about 70km it will begin to burn up in the atmosphere, however there is a chance parts of the space station will make it through and impact the ground.

However Aerospace Corp said it is highly unlikely anyone will be hit or injured when the school-bus-size space station does fall to Earth.

It is expected to land somewhere between 43 degrees north and 43 degrees south latitudes, which includes many populated areas, including the US, China, the Middle East, Africa and Australia, but rules out re-entry over the UK and much of Europe.

Although as most of the Earth is covered in water, the chances of being struck by space debris are extremely slim.

It is expected to produce a dazzling fireball when it tears across the sky and burns up in the atmosphere.

Harvard University astrophysicist Jonathan McDowell told Space.com: “Fireballs are almost certain. What happens is that there are some dense sections of the lab connected together by a rather thin structure.

“The thin structure melts first, turning the lab into a bunch – a few to a few dozen, depending – of independent pieces which melt and burn more slowly – fireballs.”